A short time later, McCain's daughter called out the vile message from the Trump supporter on Twitter.

'I wouldn't wish seeing this about your own father on my worst enemy. May God help these people who inflict such cruelty in the world,' she wrote.

Meghan McCain shut down a cruel Donald Trump supporter (pictured far right in black) who wished for her father's death ahead of the president's rally in Phoenix on Tuesday night. Reporter David Catanese tweeted out this photo shortly before 4pm Tuesday afternoon

A short time later, McCain's daughter called out the vile message from the Trump supporter on Twitter (pictured)

Arizona Sen John McCain was diagnosed with an aggressive and rare form of cancer called glioblastoma last month, just days before he was set to cast his vote against the 'skinny repeal' of Obamacare. The pair are pictured on Monday preparing to watch the solar eclipse

Trump has repeatedly clashed with McCain, even taunting the senator on his home turf in Phoenix. McCain cast the deciding no vote that killed the repeal-and-replace bill 49-51. 'One vote. Speak to your senator,' Trump said. 'Please. speak to your senator'

Arizona Sen John McCain was diagnosed with an aggressive and rare form of cancer called glioblastoma last month, just days before he was set to cast his vote against the 'skinny repeal' of Obamacare.

In a public statement, McCain suggested he did not believe the repeal would 'actually reform' the health care system or ensure coverage for individuals.

'While the amendment would have repealed some of Obamacare's most burdensome regulations, it offered no replacement to actually reform our health care system and deliver affordable, quality health care to our citizens,' McCain said at the time.

Trump has repeatedly clashed with McCain, even taunting the senator on his home turf in Phoenix.

Since McCain was diagnosed with the brain tumor, he and his daughter Meghan (pictured), have consistently posted sweet snaps during their weekly hikes

The pair spent the weekend in Cornville, Arizona, where they took this photo between August 11-13

Over the weekend, the father-daughter duo met up with former Connecticut senator Joe Lieberman (left) and South Carolina Sen Lindsey Graham (right) for a hike

In recent weeks, McCain was one of several Republicans pressuring Trump to make clear that there is not a 'moral equivalency' between white nationalists and the counter-demonstrators that turned out in Charlottesville, Virginia, on August 12.

'There's no moral equivalency between racists [and] Americans standing up to defy hate [and] bigotry. The President of the United States should say so,' McCain wrote on Twitter.

Last week, Trump slammed the 'alt-left,' which he said violently confronted neo-Nazi and white nationalist groups in Charlottesville.

That remark came after Trump claimed 'many sides' should take the blame for the clashes that erupted during the demonstrations.

Before the senator was diagnosed with cancer Trump joked about his 'crusty' condition. But upon hearing the news the president changed his tone and sent well wishes to McCain and his family.

Since McCain was diagnosed with the brain tumor, he and his daughter Meghan, have consistently posted sweet snaps during their weekly hikes.

The pair were even out and about to witness the coast-to-coast solar eclipse since on Monday.

'Watching the #SolarEclipse17 with @meghanmccain on a hike in #Arizona!' the senator wrote on Twitter.

Over the weekend, the father-daughter duo met up with former Connecticut senator Joe Lieberman and South Carolina Sen Lindsey Graham for a hike.